Matas Seimys, Developer in Vilnius, Vilnius County, Lithuania
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Matas Seimys

Verified Expert  in Engineering

Software Developer

Vilnius, Vilnius County, Lithuania

Toptal member since September 17, 2020

Expertise
Back-end DevelopersFull-stackWeb DevelopmentFront-endLinuxPythonGitJavaScriptCSSDjangoReact.jsFlaskREST APIReduxTypeScript
Bio

Matas is a full-stack software engineer who likes to tinker with continuous integration and deployment pipelines. He a Certified Scrum Master and PMP with a passion for smooth user experiences, code clean, and quality. Not satisfied with a simple "it works," Matas pushes the envelope to deliver truly exceptional work. He created an X-ray image processing system and a self-service machine learning workflow. He is open to new ideas and loves a good challenge.

Portfolio

Genus AI
JavaScript, TypeScript, Python, Amazon Web Services (AWS), SQL...
Polltix
Next.js, React, Styled-components, Django, Django REST Framework, Pandas...
Oxipit
Amazon Web Services (AWS), GitLab CI/CD, TypeScript, SaltStack, Flask, DICOM...

Experience

  • Python - 13 years
  • JavaScript - 10 years
  • Django - 7 years
  • React - 5 years
  • Machine Learning - 4 years
  • TypeScript - 3 years
  • Docker - 3 years

Availability

Part-time

Preferred Environment

Amazon Web Services (AWS), Machine Learning, Docker, SQL, TypeScript, React, JavaScript, Django, Python, Linux

The most amazing...

...product I've delivered was a scientific document management system.

Work Experience

Senior Software Engineer

2020 - PRESENT
Genus AI
  • Split and redesigned the whole front end of a monolithic application. I introduced a single-page application written in TypeScript using the React framework that is connected via the GraphQL layer and the setup of a CI/CD pipeline.
  • Created a templated builder based on an HTML canvas (Fabric.js library). It allows users to create SVG-based ad templates with dynamic images and is used for dynamic catalog ads with over 100,000 items inside.
  • Refactored a Python (Django) back end to use the GraphQL API. Worked on multiple integrations with Auth0, Stripe payments, Shopify, and Facebook/Meta.
Technologies: JavaScript, TypeScript, Python, Amazon Web Services (AWS), SQL, Amazon Elastic Container Service (ECS), GitHub, React, Django, FastAPI, GraphQL, Front-end, Recharts, Celery, RESTFul APIs

Co-founder and CTO

2020 - 2024
Polltix
  • Created a front end in Next.js and a back end in Django and integrated with Maps, Facebook, and Google. As a result, there were 16,000+ unique registered users.
  • Calculated poll inclusivity scores using pandas based on self-reported political voting preferences and demographic features.
  • Contributed to internationalization and localization into many deployment languages.
Technologies: Next.js, React, Styled-components, Django, Django REST Framework, Pandas, Ansible, Front-end, GitHub, RESTFul APIs

Senior Software Engineer

2019 - 2020
Oxipit
  • Migrated from a static application to a single page web application using React, Redux, Webpack, Jest, and Puppeteer.
  • Created a GitLab CI/CD workflow where Docker images are built, and unit/integration tests are executed. A central repository of images to deploy for clients is maintained.
  • Managed SaltStack that controls many deployments across different establishments under various VPN setups.
  • Refactored a TensorFlow-based deep learning application to be better aligned with SOLID principles and support multiple languages and image outputs.
Technologies: Amazon Web Services (AWS), GitLab CI/CD, TypeScript, SaltStack, Flask, DICOM, TensorFlow, OpenCV, SQL, Django, Python, Back-end, CI/CD Pipelines, Front-end, GitHub, RESTFul APIs

Software Engineer Team Lead

2017 - 2018
Revel Systems
  • Maintained and extended a Revel POS back end written in Python (Django), adding integrations and customizations.
  • Drove online ordering software bug fixing and refactoring.
  • Led a team responsible for customer identity microservice.
  • Drove the initial design and creation of an enterprise product and price management software that integrates with the Revel System POS.
Technologies: Amazon Web Services (AWS), Backbone.js, React, PostgreSQL, Docker, RabbitMQ, Django, Python, Back-end, CI/CD Pipelines, GitHub, Celery, RESTFul APIs

Software Developer

2015 - 2017
Adform
  • Developed a new interface using React to set up marketing campaigns.
  • Created a builder for alerts using TypeScript/React. Alerts are triggered when certain thresholds have been reached.
  • Created a traveling expense management software using Python (Django) and JavaScript.
Technologies: Python, Jira, Scrum, TeamCity, TypeScript, Redux, React, Back-end, GitHub

Software Developer

2011 - 2015
VTeX
  • Developed an application to edit and submit scientific article corrections online: https://vtex.lt/services/skylatex-proofing/.
  • Improved production efficiency by creating internal tools to speed-up scientific article processing-Python GUI to execute scripts, and track changes.
  • Built integration scripts to upload and download data from an FTP, and sync with the cloud.
Technologies: Python, Flask, Django, JavaScript, Amazon Web Services (AWS), Docker, MongoDB, LaTeX, Back-end

Experience

Peckis

https://github.com/mseimys/peckis
Developed an ML back end (Python, Flask, OpenCV, TensorFlow) and front end (create-react-app) program that enables the recognizing of hand-written digits. This project was meant to test DevOps/educational purposes as a minimal working example with all the moving parts needed for a machine learning workflow.

Food Delivery Application

https://github.com/mseimys/fooda
An application that uses React and TypeScript on the front end with Django and Python on the back end to test various deployment scenarios. Features inclued the ability to create an account and log in. There are two roles; one for regular users who see all participating restaurants and can place orders, and restaurant owners who have the ability to manage restaurants and menu items. Orders can be in variuos states; placed, canceled, processing, on route, delivered, and received. As a userful bonus, restaurant owners can block a misbehaving users.

Polltix

An application that enables politicians to generate sharable links with questions and quickly poll their constituents. A link can then be shared via Facebook or other social networks. The application generates statistical reports to help better understand opinions and their distributions.

Education

2006 - 2008

Master's Degree in Biophysics

Vilnius University - Vilnius, Lithuania

2002 - 2006

Bachelor's Degree in Theoretical and Mathematical Physics

Vilnius University - Vilnius, Lithuania

Certifications

AUGUST 2016 - MAY 2018

Certified Scrum Master

Scrum Alliance

JUNE 2010 - MAY 2016

PMP (Project Management Professional)

Project Management Institute

Skills

Libraries/APIs

React, REST APIs, TensorFlow, OpenCV, Backbone.js, Node.js, Pandas, Recharts

Tools

Git, GitLab CI/CD, Webpack, Celery, SaltStack, RabbitMQ, TeamCity, Jira, LaTeX, Amazon Elastic Container Service (ECS), GitHub, Ansible

Languages

Python, JavaScript, CSS, HTML, TypeScript, GraphQL, SCSS, SQL

Frameworks

Django, Flask, Redux, Next.js, Django REST Framework

Paradigms

REST, Scrum

Platforms

Linux, Docker, Amazon Web Services (AWS)

Storage

PostgreSQL, MongoDB

Other

Full-stack, Web Development, Back-end, Front-end, RESTFul APIs, CI/CD Pipelines, FastAPI, Machine Learning, Physics, Mathematics, Computational Biological Physics, Certified ScrumMaster (CSM), Project Management Professional (PMP), DICOM, Apollo, Styled-components

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